The 200 envelopes purchased all had insufficient glue to actually secure the envelope for closing properly. We had to add either tape or white glue to secure the envelopes. Terrible quality control. I would NOT recommend this product.
It's an envelope so what can you say? Sturdy and reliable. I nave found that if they are not used for a while (how long I am not sure but at least a year) the gummed flap loses its stickiness and you have to tape the flap shut. Otherwise AOK
These envelopes are made poorly. It is annoying trying to insert a letter into this envelope. It must have been made by the lowest bidder because it is not made the same as the last box I bought. The edge of the envelope under the flap catches the letter when trying to insert it. This did not happen with the last box.